Disk Drive Carriers And Mountable Hard Drive Systems With Improved Air Flow

ABSTRACT

The side profile of a hard drive assembly may be configured with one or more open areas to allow cooling air to pass side-to-side through a lateral flow channel provided by a cavity defined in the base portion of the hard drive assembly. Corresponding and complementary open areas may be also be defined in mating drive carrier assembly side components to allow passage of lateral side-to-side cooling air through the base portion flow channel of a hard drive assembled to the drive carrier assembly to form a mountable hard drive system that is installed into a storage enclosure. The at least partially aligned open flow areas of the assembled hard dive assembly and drive carrier assembly may cooperate to reduce air flow impedance across multiple rows of hard drive systems through a storage enclosure.

RELATED APPLICATIONS

This application is a divisional of pending U.S. patent application Ser.No. 14/023,939, filed on Sep. 11, 2013 and entitled “Disk Drive CarriersAnd Mountable Hard Drive Systems With Improved Air Flow”, the entiredisclosure of which is incorporated herein by reference.

The present application is related in subject matter to patentapplication Ser. No. 14/023,991 filed Sep. 11, 2013, entitled “HARD DISKDRIVE ASSEMBLIES WITH OPEN SIDE WALL AREAS” by Mundt et al., which isincorporated herein by reference in its entirety.

FIELD OF THE INVENTION

This invention relates generally to information handling systems and,more particularly, to disk drive carriers and mountable hard drivesystems for information handling systems.

BACKGROUND OF THE INVENTION

As the value and use of information continues to increase, individualsand businesses seek additional ways to process and store information.One option available to users is information handling systems. Aninformation handling system generally processes, compiles, stores,and/or communicates information or data for business, personal, or otherpurposes thereby allowing users to take advantage of the value of theinformation. Because technology and information handling needs andrequirements vary between different users or applications, informationhandling systems may also vary regarding what information is handled,how the information is handled, how much information is processed,stored, or communicated, and how quickly and efficiently the informationmay be processed, stored, or communicated. The variations in informationhandling systems allow for information handling systems to be general orconfigured for a specific user or specific use such as financialtransaction processing, airline reservations, enterprise data storage,or global communications. In addition, information handling systems mayinclude a variety of hardware and software components that may beconfigured to process, store, and communicate information and mayinclude one or more computer systems, data storage systems, andnetworking systems.

Information handling systems include enterprise storage systems. Toincrease rack level drive density for enterprise storage systems, thequantity of hard drives contained within drive enclosures for enterprisestorage systems has increased over time. In the past, racked storageenclosure form factors often had a single row of hard drives that wereinserted from the front of the system, and storage controllers and powersupplies were then inserted from the rear of the system. These existingfront load systems hold the single row of drives in a position such thatfresh air drawn in from a rear-positioned fan flows from front-to-backacross the length of each drive in the single row.

FIG. 1 illustrates a bottom perspective view of a conventional harddrive (3.5 inch HDD) assembly 100 having a cavity 110 that is defined inthe bottom surface 102 of the base portion 160 of the casting of thehard drive assembly 100. As shown, drive assembly 100 has a front end132, a back end 134, and two opposing side walls 136 and 138. Threadedmounting holes 105 are defined in the opposing side walls 136 and 138 ofdrive assembly 100 to receive complementary threaded fasteners thatserve the purpose of securing a drive carrier assembly to the hard driveassembly 100 as further described herein. In FIG. 1, the top portion 150of the drive assembly 100 is a sealed space that contains the drivemedia and read/write arm (heads). The base portion 160 of the driveassembly 100 (delineated from top section 150 by dashed lines) generallyconsists of a drive controller printed circuit board (PCB) assembly 152,a motor housing 153, and has protrusions/ribs 154 for bearings andstiffening features. The base portion 160 is configured to performmultiple roles for the drive assembly 100, including providingshock/rotational vibration (RV)/dynamics dampening, thermal dissipation,front-to-back (longitudinal) air flow, and head/disk interface (HDI)stability.

As shown in FIG. 1, ribs 154 are not sized to be the full height of thedrive's casting (i.e., they do not extend to the match the full heightof the side walls 136 and 138 of base portion 160). In this regard, theheight of ribs 154 is reduced relative to the side walls 136 and 138 tooptimize for longitudinal (front-to-back) air flow when drive assembly100 is deployed in a conventional front load single row drive enclosuresystem. The side walls 136, 138 of the drive assembly 100 are fullheight so that the bottom surface of the side walls 136, 138 provides aprimary measuring datum for the drive assembly 100. Additionally, manyenclosure designers utilize the bottom surface of a drive assembly 100as a constraint for drive mounting or for drive rails.

FIG. 2 shows the hard drive assembly 100 of FIG. 1 as it may bemechanically coupled to two side components (rails) 202 and 204 of adrive carrier assembly 200 by threaded mounting screws 106 receivedthrough mounting holes 107 of drive carrier assembly 200 into threadedmounting holes 105 of drive assembly 100 to form a conventionalmountable hard drive system 250. As shown, side mounting rails 202 and204 of drive carrier assembly 200 are configured to slide along acontiguous rail surface of side walls 138 and 136 of hard drive assembly100 between the fastener holes 105. As further shown in FIG. 2, drivecarrier side components 202 and 204 are configured to support a crossmember in the form of a drive handle mechanism 220 there between thatallows for insertion and removal of front end 132 of drive assembly 100from mating relationship with a corresponding mechanism within the driveenclosure that is configured to mount and secure the drive assembly 100in operable engagement within the drive enclosure. When deployed withina conventional front-loading single row drive enclosure, some coolingairflow advantage is realized due to airflow tunneling fromfront-to-back through the cavity 110 defined in the bottom surface 102of the base portion 160 drive assembly 100 as shown by the arrows 290 inFIG. 2.

To gain more drive density, a new class of racked storage denseenclosure has emerged having a form factor that utilizes a drive drawerthat is filled with rows of hard drives. FIG. 3 illustrates a cut-awayperspective view of one example of drawer and drive components of aconventional drawer-based dense storage drive enclosure 300. As shownenclosure 300 includes a drawer 320 having multiple and parallel rows310 of closely-spaced hard drive assemblies 100 and their respectivecorresponding drive carrier assemblies 200 that are orientedside-to-side across the drawer of the enclosure 300, with rear-mountedcooling fans 390 that draw fresh cooling air 350 into the enclosure 300from the front of the enclosure 300 and expel the warmed cooling air 352from the back of the enclosure 300. For illustration purposes, chassisenclosure walls that surround drawer 320 and rows 310 of hard drivesystems 250 are not shown in FIG. 3. Most of such conventionaldrawer-based implementations are designed for vertical top loadedinsertion of the mountable hard drive systems 250 into the drawer 320,i.e., the hard drive systems 250 are loaded vertically from the top intothe drawer 320 of the storage enclosure 300 in a toaster-style fashionwith the front 132 of the drive assemblies 100 facing upwards and withone side wall 136 or 138 facing toward the front of the enclosure.

As further shown in FIG. 3, this vertical drive-loading configurationcreates airflow and cooling problems for the multiple rows 310 a to 310f of hard drive assemblies 100. When a hard drive system 250 is insertedin a vertical fashion in a dense system enclosure, the solid side wallprofiles 136 and 138 of the drive assembly 100 and solid side profilesof side components (rails) 202 and 204 of carrier assembly 200completely block the lateral (side-to-side) flow of cooling air throughthe drive assemblies as shown by arrows 292 in FIG. 2. The only pathwaysfor air flow through each row of drive assemblies of the dense enclosuredrawer is through any provided gaps 398 existing between differentadjacent drive assemblies 100 of each row 310 and through any providedgaps 399 present between the enclosure walls and the ends of the rows310 as shown in FIG. 3.

Due to the multiple side-to-side orientation of the rows of hard drivesystems 250, only the front-most row 310 a of hard drive assemblies 100receives fresh cooling air 350 from the front-positioned cooling fans,while each successive row 310 b to 310 f of drive assemblies 100 towardthe rear of the enclosure receives pre-heated air that has alreadyflowed across the previous row/s of hard drive assemblies 100 in theenclosure. At the same time, the close spacing of the hard drive systems250 within each row acts to restrict the flow of air across the row 310due to the solid mass of the full-height side walls 136, 138 of theindividual drive assemblies 100 that are closely spaced together withineach row. This results in an overall reduction in rate of cooling airflow across the drive assemblies 100 of the enclosure. Increasing thegap size between adjacent hard drive systems 250 in the same row 310more allows for more air flow, but reduces the number of hard drivesystems 250 that can be installed in the dense enclosure system. Thus,airflow requirements conflict with drive density desires in conventionaldense enclosure systems.

SUMMARY OF THE INVENTION

Disclosed herein are systems and methods that may be implemented toprovide open areas in the opposing side walls of a hard disk driveassembly to optimize lateral (side-to-side) cooling air flow across ahard disk drive assembly in a storage enclosure or other type of harddrive enclosure (e.g., such as server chassis) by providing a flowchannel defined within the base portion of the disk drive assembly todecrease impedance of lateral air flow across the disk drive assemblyand through the hard drive enclosure.

In one exemplary embodiment, the side profile of a hard drive assemblymay be configured with one or more open areas (e.g., with a series ofholes or a series of notches defined in the side walls or rails of thedrive assembly base portion) to allow air to pass side-to-side through alateral flow channel provided by a cavity defined in the base portion ofthe drive assembly. In this way, the air may pass through the lateralflow channel and towards and contacting areas of the bottom surface ofthe drive assembly located between the sides of the hard drive assembly.Corresponding and complementary open areas in the form of air flowinlet/s and outlet/s may be also be defined in mating drive carrierassembly side components to allow passage of lateral side-to-sidecooling air through the base portion flow channel of a mated driveassembly when the mated hard drive assembly and drive carrier assemblyare installed together as a mountable hard drive system into a harddrive enclosure. In one embodiment, the provided lateral flow channelmay be further implemented in a manner that results in substantially noloss to other functionalities of the drive assembly base portion, suchas dynamic dampening, thermal dissipation, and HDI. The disclosedsystems and methods may also be implemented in one embodiment in amanner that reduces air flow impedance across hard drive systems andthrough a storage enclosure (as compared to the air flow impedanceacross conventional hard drive systems similarly oriented and containedin a storage enclosure) in order to achieve both reduced cooling fanpower costs and increased cooling efficiency for an individual driveassembly as well as to achieve increased cooling efficiency on a systemlevel for multiple drive assemblies deployed in a dense storageenclosure.

In one exemplary embodiment, open area/s in the form of one or moreopenings (e.g., holes, notches, recesses, cut-outs, etc.) may be definedin the side walls or rails of the drive assembly base portion that areconfigured for at least partially overlapping or aligning with an openarea (e.g., one or more corresponding openings, notches, recesses,cut-out areas, etc.) provided by mating drive carrier side components ofa drive carrier assembly when the drive carrier assembly is assembled tothe drive assembly as a mountable hard drive system in order to enableadditional flow of air, for example, to provide additional air flowspace to supplement the minimal air flow space in the gap betweenmounted hard drive systems of a hard drive enclosure. For example, inone exemplary embodiment, openings or notches may be defined in thedrive assembly that mimic (i.e., copy or match) the pattern of openingsand/or notches defined in the drive assembly casting. In anotherexemplary embodiment, open area may be defined in the side walls of adrive assembly that are configured to align with a drive carrierassembly above the depth of a provided notch in a drive carrier sidecomponents or a lowered drive carrier side wall of a mated drive carrierassembly when the two components are assembled together as a mountablehard drive system.

In one respect, disclosed herein is a mountable hard drive system,including a hard drive assembly and a drive carrier assembly. The harddrive assembly may include: a front end, a back end, and two opposingside walls extending between the front end and back end of the harddrive assembly, a bottom surface having a drive cavity defined thereinbetween the two opposing side walls, and at least one open area definedin each of the opposing side walls, the open area of each side wallbeing in fluid communication with the drive cavity. The drive carrierassembly may include two opposing side rail components, each of the siderail components having at least one air flow area defined therein. Eachgiven one of the two side rail components of the drive carrier assemblymay be mechanically coupled to a different one of the two opposing sidewalls of the hard drive assembly such that the open flow area of thegiven side rail component is at least partially aligned with the openflow area of the given one of the opposing side walls of the hard driveassembly to form an air flow channel across the drive cavity of the harddrive assembly between the two opposing side walls and the two opposingside rail components.

In another respect, disclosed herein is a hard drive enclosure system,including at least one hard drive system mounted within the hard driveenclosure, the mountable hard drive system including a hard driveassembly and a drive carrier assembly mechanically coupled to the harddrive system. The hard drive assembly may include: a front end, a backend, and two opposing side walls extending between the front end andback end of the hard drive assembly, a bottom surface having a drivecavity defined therein between the two opposing side walls, a topsurface opposite the bottom surface, and at least one open area definedin each of the opposing side walls, the open area of each side wallbeing in fluid communication with the drive cavity. The drive carrierassembly may include two opposing side rail components, each given oneof the side rail components having at least one air flow area definedtherein and being mechanically coupled to a different one of the twoopposing side walls of the hard drive assembly such that the open flowarea of the given side rail component is at least partially aligned withthe open flow area of the given one of the opposing side walls of thehard drive assembly to form an air flow channel across the drive cavityof the hard drive assembly between the two opposing side walls and thetwo opposing side rail components. The hard drive enclosure system mayfurther include: multiple enclosure walls surrounding the hard drivesystem, and a cooling air flow source configured to induce lateralside-to-side flow of cooling air through the flow channel of the harddrive system across the drive cavity of the hard drive assembly betweenthe two opposing side walls and the two opposing side rail components.

In another respect, disclosed herein is a method of cooling at least onemountable hard drive system that includes a hard drive assemblymechanically coupled to a drive carrier assembly, the method includingproviding cooling air to the mountable hard drive system. The hard driveassembly may include: a front end, a back end, and two opposing sidewalls extending between the front end and back end of the hard driveassembly, a bottom surface having a drive cavity defined therein betweenthe two opposing side walls, and at least one open area defined in eachof the opposing side walls, the open area of each side wall being influid communication with the drive cavity. The drive carrier assemblymay include two opposing side rail components, each of the side railcomponents having at least one air flow area defined therein, and whereeach given one of the two side rail components of the drive carrierassembly is mechanically coupled to a different one of the two opposingside walls of the hard drive assembly such that the open flow area ofthe given side rail component is at least partially aligned with theopen flow area of the given one of the opposing side walls of the harddrive assembly to form an air flow channel across the drive cavity ofthe hard drive assembly between the two opposing side walls and the twoopposing side rail components. The method may further include using acooling air flow source to induce lateral side-to-side flow of coolingair through the flow channel of the hard drive system across the drivecavity of the hard drive assembly between the two opposing side wallsand the two opposing side rail components.

In another respect, disclosed herein is a drive carrier assemblyconfigured for mechanically coupling to a hard drive assembly to form amountable hard drive system, the drive carrier system including twoopposing side rail components, each of the side rail components havingat least one air flow area defined therein. Each given one of the twoside rail components of the drive carrier assembly may be configured tobe mechanically coupled to a different one of two opposing side walls ofa hard drive assembly that itself has: a front end, a back end, and twoopposing side walls extending between the front end and back end of thehard drive assembly, a bottom surface having a drive cavity definedtherein between the two opposing side walls, and at least one open areadefined in each of the opposing side walls, the open area of each sidewall being in fluid communication with the drive cavity. Each given oneof the two side rail components of the drive carrier assembly may beconfigured to be mechanically coupled to a different one of the twoopposing side walls of the hard drive assembly such that the open flowarea of the given side rail component is at least partially aligned withthe open flow area of the given one of the opposing side walls of thehard drive assembly to form an air flow channel across the drive cavityof the hard drive assembly between the two opposing side walls and thetwo opposing side rail components.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a bottom perspective view of a conventional harddrive assembly.

FIG. 2 illustrates a bottom perspective view of a conventional mountablehard drive system.

FIG. 3 illustrates a cut-away perspective view of a conventionaldrawer-based dense storage drive enclosure.

FIG. 4 illustrates a bottom perspective view of a hard drive assemblyaccording to one exemplary embodiment of the disclosed systems andmethods.

FIG. 5A illustrates a bottom perspective view of a mountable hard drivesystem according to one exemplary embodiment of the disclosed systemsand methods.

FIG. 5B illustrates a bottom exploded perspective view of components ofa mountable hard drive system according to one exemplary embodiment ofthe disclosed systems and methods.

FIG. 6A illustrates a cut-away perspective view of a dense storage driveenclosure according to one exemplary embodiment of the disclosed systemsand methods.

FIG. 6B illustrates a cut-away top view of a dense storage driveenclosure according to one exemplary embodiment of the disclosed systemsand methods.

FIG. 7 illustrates a side perspective view of a row of three mountablehard drive systems according to one exemplary embodiment of thedisclosed systems and methods.

FIG. 8 illustrates a comparative graph of simulated air flow impedanceversus air flow rate.

DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

FIG. 4 illustrates one exemplary embodiment of a hard drive assembly 400(e.g., such as a 3.5 inch HDD) having a cavity 410 that is defined inthe bottom surface 402 of the base portion 460 of the casting (e.g.,metal casting) of the hard drive assembly 400. Not shown is the opposingtop surface of hard drive assembly 400 that may in one embodiment be asubstantially flat and solid surface, e.g., with no cavity definedtherein. As shown, drive assembly 400 has a front end 432, a back end434, and two opposing side walls 436 and 438. Threaded mounting(fastener) holes 405 are defined in the opposing side walls 436 and 438of drive assembly 400 to receive complementary mating threaded fasteners506 for secureably mounting a drive carrier assembly to hard driveassembly 400 as described further herein. In the exemplary embodiment ofFIG. 4, a solid planar wall portion 411 of bottom surface 402 delineatesand separates a hermetically sealed top section 450 from the cavity 410of base portion 460 of the hard drive assembly.

In FIG. 4, the top portion 450 of the drive assembly 400 is ahermetically sealed space that contains the drive media and read/writearm (heads). The base portion 460 of the drive assembly 400 (delineatedfrom top section 450 by dashed lines) generally includes a drivecontroller PCB assembly 452 including drive controller circuitryadjacent the front end 432, a drive motor housing 453, and hasprotrusions/ribs 454 extending from wall portion 411 of bottom surface402 and radiating from drive motor housing 453 for bearings andstiffening features. In one embodiment, hard drive assembly 400 may havea lateral (minor axis) dimension of about 3.5 inches wide measuredbetween side walls 436 and 438, and a longitudinal (major axis)dimension of about 6 inches long measured between front end 432 and backend 434, although it is possible that a hard drive assembly 400 may havea form factor of any other size or shape (e.g., larger or smaller).

As shown in embodiment of FIG. 4, side walls 436 and 438 of base portion460 of hard drive assembly 400 may be configured with open areas toallow cooling air to pass laterally from side-to-side between side walls436 and 438 through a flow channel defined in the base portion 460 ofthe hard drive assembly 400. For example, in the exemplary embodiment ofFIG. 4, open areas in the form of multiple circular air flow openings480 (e.g., multiple holes drilled through side walls 436 and 438 thatare separate and different from the mounting holes 405) are defined ineach of side walls 436 and 438 in fluid communication with cavity 410 soas to allow flow of cooling air into and out of cavity 410 of the baseportion 460 of hard drive assembly 400. In this embodiment, the openings480 are defined in the drive side wall casting relatively low on thedrive assembly (i.e., in the base portion 460) and are defined inpositions that are partially in line with threaded mounting holes 405 asshown, although any other suitable alternative forms of mountingtechnology may be employed to secure a drive carrier assembly 200 to ahard drive assembly 100. Openings 480 are also illustrated as beinglongitudinally-aligned with each other along the side rails 436 and 438,although such alignment is not required in al embodiments.

It will be understood that the number and size of open areas (such asair flow openings 480) may vary and in one embodiment may be selected toprovide a total open area (e.g., total open air flow area) in the sideof a hard drive assembly side wall to achieve a desired air flowcapacity through a hard drive assembly cavity during operation. Forexample, in one exemplary embodiment, the number and size of air flowopenings 480 defined to extend through each of side walls 436 and 438 ofbase portion 460 may be selected to provide a total combined open areathrough the given side wall that represents at least about 20% of thetotal dimensional side area of each of side walls 436 and 438 of baseportion 460, alternatively at least about 30% of the total dimensionalside area of each of side walls 436 and 438 of base portion 460,alternatively from about 20% to about 60% of the total dimensional sidearea of each of side walls 436 and 438 of base portion 460,alternatively from about 30% to about 60% of the total dimensional sidearea of each of side walls 436 and 438 of base portion 460,alternatively from about 20% to about 50% of the total dimensional sidearea of each of side walls 436 and 438 of base portion 460, and furtheralternatively from about 30% to about 50% of the total dimensional sidearea of each of side walls 436 and 438 of base portion 460. However, itis also possible that total combined open area through the given sidewall that may represents less than about 20%, or greater than about 60%of the total dimensional side area of each of side walls 436 and 438 ofbase portion 460. In one embodiment, the range or particular value ofcombined open area as a percentage of the total dimensional side area ofeach of side walls 436 and 438 of base portion 460 may be selected so asnot to impact other drive performance characteristics, such as dynamicperformance and thermal performance.

It will be understood that the above-noted total dimensional side areaof each of side walls 436 and 438 of base portion 460 refers to thesurface area defined along the length of each of the side walls 436 and438 of base portion 460 (as illustrated by cross-hatching of the totaldimensional side area of side wall 436 of base portion 460 in FIG. 4)which is defined between the respective bottom surfaces 560 and 562 ofthe side walls 436 and 438 and the projected line of intersection ofwall portion 411 with each of side walls 436 and 438.

Still referring to FIG. 4, ribs 454 are sized so as not to extend fromwall portion 411 to the full height of the drive's casting (i.e., theydo not extend to the match the full height of the side walls 436 and 438of base portion 460), for example leaving a space of about 0.8 inches inone exemplary embodiment between the bottom surface 560 of the rails andthe bottom surface 562 of the side walls 436 and 438 of base portion460, although any other relative height of ribs 454 relative to heightof side walls 436 and 438 may be employed to achieve a lateral(side-to-side) flow channel through base portion 460. This created flowchannel allows for side-to-side cooling air flow through openings 480and across cavity 410 when drive assembly 400 is deployed in a densestorage enclosure or any other hard drive enclosure configuration havingside impinging cooling air flow. As shown, the perforated side walls436, 438 of the drive assembly 400 are full height so that the bottomsurface of the sidewalls 436, 438 provide a primary measuring datum forthe drive assembly 400 while at the same time also providing inletopenings 480 and outlet openings 480 to allow a lateral side-to-sidecooling air flow through the channel in base portion 460 of driveassembly 400.

FIG. 5A shows the hard drive assembly 400 of FIG. 4 as it may bemechanically coupled to two side rail components 502 and 504 of a drivecarrier assembly 500 by threaded mounting screws 506 received throughmounting holes 507 of drive carrier assembly 200 into threaded mountingholes 405 of drive assembly 400 to form a mountable hard drive system550. FIG. 5B is an exploded view showing hard drive assembly 400 anddrive carrier assembly 500 in position for assembly together. As furthershown in FIGS. 5A and 5B, drive carrier side components 502 and 504 ofthis exemplary embodiment are configured to support a cross member inthe form of a drive handle and bezel mechanism 520 there between thatallows for insertion of front end 432 of drive assembly 400 into a driveenclosure and for subsequent removal therefrom, e.g., in a hot-pluggablemanner. In this regard front end 432 of drive assembly 400 may beinserted into mating relationship with a corresponding electrical andmechanical interconnect mechanism within a drive enclosure that isconfigured to mechanically secure the drive assembly 400 in operableelectrical engagement within the drive enclosure. Drive carriercomponents 502, 504 and 520 may be constructed of any suitably strongmaterial (e.g., metal, plastic, etc.).

In the illustrated embodiment of FIGS. 5A and 5B, each of drive carrierside components 502 and 504 may be configured with a reduced crosssection 506 to define a recessed open area 580 in drive carrier sidecomponents that are positioned adjacent and that at least partiallyoverlap the multiple air flow openings 480 defined in each of side walls436 and 438 of base portion 460 to allow access for flow of cooling air570 into and out of openings 480 of respective sidewalls 438 and 436when attached to respective side components 502 and 504 of drive carrierassembly 500 as shown. Drive carrier side component 504 is not fullyvisible in FIG. 5A, but as shown in FIG. 5B it may be similarlyconfigured as side component 502, e.g., with a recessed open area 570disposed adjacent the multiple air flow openings 480 defined in sidewall 436 of base portion 460 to allow access for flow of cooling air 570into or out of openings 480 of sidewall 436. Thus, when multipleadjacent rows of hard drive systems 550 are inserted or otherwisemounted into a drawer-based dense storage drive enclosure 600 such asillustrated in FIG. 6, lateral side-to-side flow of cooling air 570through the base portion 460 of each drive assembly 400 of each ofadjacent rows 310 may be achieved as further shown and described hereinin relation to FIG. 6.

FIG. 6A illustrates a cut-away perspective view of one exemplaryembodiment of drawer and drive components of a drawer-based densestorage drive enclosure 600 according to the disclosed systems andmethods. FIG. 6B illustrates a cut-away top view of the enclosureembodiment of FIG. 6A. Storage drive enclosure 600 may be operativecoupled, for example, to an information handling system as part of anenterprise storage system such as a redundant array of independent disks(RAID) storage system. Further information on RAID systems may be found,for example, in United States Patent Application Publication2012/0110262, which is incorporated herein by reference in its entiretyfor all purposes. It will be understood that a RAID storage systemenvironment is just one example embodiment, and that the disclosedsystems and methods may be implemented in any other storage or otherinformation handling system application that employs one or more harddisk drive assemblies.

As shown in FIGS. 6A and 6B, enclosure 600 includes a drawer assemblythat supports multiple and parallel rows 610 a to 610 f ofclosely-spaced hard drive systems 550 (including hard drive assemblies400 assembled to their corresponding drive carrier assemblies 500)mounted in a side-to-side orientation across the drawer of the enclosure600, with rear-mounted cooling fans 690 that draw fresh cooling air 570into the enclosure 600 through an air-permeable front chassis wall 614(e.g., grill, perforated sheet, etc.) of the enclosure 600 and expel thewarmed cooling air 572 from the back of the enclosure 600. In thisembodiment, the multiple rows 610 of hard drive systems 550 are arrangedso that one or both of the side walls of the individual hard drivesystems 550 of a first one of the multiple rows 610 of hard drivesystems 550 faces the side walls of respective individual hard drivesystems 550 of an adjacent one of the multiple rows 610 of hard drivesystems 550. As further shown, the multiple rows 610 of hard drivesystems 550 are also arranged such that the cooling fans 690 areconfigured to induce lateral side-to-side flow of cooling air firstthrough the flow channel of each given one of the two or more hard drivesystems 550 of a first one of the multiple rows (e.g., such as row 610a) of hard drive systems 550 that is closer to the cooling air inlet 614and then subsequently through the flow channel of each given one of thetwo or more hard drive systems 550 of a second and downstream (ordownwind) one of the multiple rows (e.g., such as row 610 b-610 f) ofhard drive systems that is further from the cooling air inlet 614 thanthe first one of the multiple rows 610.

As illustrated, enclosure 600 also includes chassis enclosure side walls611 and chassis lid 612 that together with chassis enclosure basesurface 613 surround rows 610 to form a cooling air flow seal around therows 610 of mounted drive assemblies 400. Such a storage enclosure 600may be configured for operatively storing multiple hard drive systems550 in any suitable manner with one side wall 136 or 138 of each driveassembly 400 facing toward the front of the enclosure 600, e.g.,top-loadable through removable lid 612, top-loadable into pull outdrawer, front-loadable through removable front chassis wall 614, orloadable using any other suitable manner.

As further shown in FIGS. 6A and 6B, during operation of storage freshcooling air 570 is drawn into enclosure 600 through air-permeable frontwall 614 by virtue of suction action of rear cooling fans 572, and flowsfirst into the side-wall air flow openings 480 and though the cavity 410of each of the drive assemblies 400 of first row 610 a. In one exemplaryembodiment, drive assemblies 400 may be contained within enclosure 600such that openings 480 of each of drive assemblies 400 of each ofsubsequent rows 610 b to 610 f may be longitudinally aligned with eachother, e.g., such that openings 480 defined in side walls 436 of each ofdrive assemblies 400 of row 610 a are substantially aligned withopenings 480 defined in facing side walls 438 of each of driveassemblies 400 of row 610 b so as to allow direct passage of cooling air570 between drive assemblies 400 as cooling air 570 moves from first row610 a of drive assemblies 400 to the last row 610 f of drive assemblies400. In such an embodiment, cooing air 570 successively flows into theside-wall air flow openings 480 and though the cavity 410 in baseportion 460 of each of the subsequent drive assemblies 400 of rows 610 bto 610 f before exiting out rear side 615 of enclosure 570 due to actionof rear cooling fans 572 as shown by dashed air flow arrows in FIG. 6B.In this manner, each of drives 400 is cooled by cooling air passingthrough its respective cavity 410 in a manner that is not possible withconventional mounted drive assemblies 100 of FIGS. 1 and 2 in which thesolid side wall profile (136 or 138) of the drive assembly 100completely blocks the lateral (side-to-side) flow of air through thedrive assemblies as shown by arrows 292 in FIG. 2.

Still referring to the exemplary embodiment of FIGS. 6A and 6B, gaps 698between individual hard drive systems 550 of each row 610 may vary basedon characteristics of a given system, and may be of sufficient width(e.g., in one exemplary embodiment about 4 millimeters, or any othersuitable greater or lesser width) to conduct at least a portion of airflow 570 between individual drive assemblies 400 of hard drive systems550, although this is not necessary since cooling air flow 570 isallowed to pass through the openings 480 and cavities 410 of theindividual drive assemblies 400. In this regard, it will be understoodthat greater air flow through the openings 480 and cavities 410 of theindividual drive assemblies 400 of a given system allows reduced size ofgaps 698 to be employed to achieve particular thermal goals for thatsystem. Thus, in one exemplary embodiment, adjacent hard drive systems550 of a given row 610 may be mounted back-to-back within enclosure 600with substantially no gap existing between individual hard drive systems550, maximizing the use of space and maximizing the drive density byincreasing the number of drives 400 that may be contained within a giveninterior volume of a storage enclosure 600 while at the same timeproviding sufficient cooling for the drive assemblies 400 duringoperation of the storage system.

It will be understood that the configuration of storage drive enclosure600 of FIGS. 6A and 6B is exemplary only and that the disclosed harddrive systems 550 may be mounted into any other configuration of storageenclosure with any other configuration and/or location of cooling airflow source that induces lateral side-to-side of cooling air flow sourceacross one or more of the mounted drives 400. For example, it ispossible that one or more rows of hard drive systems 550 may belongitudinally-oriented with their sides 436 and 438 facing the sides ofa drive enclosure assembly that is configured to provide cooling airflow from one side of the enclosure to the other side of the enclosureacross the drives 400 (i.e., rather than from front to back). Moreover,in addition to drawer-type dense storage drive enclosures, the disclosedhard drive systems 550 may be mounted into hard drive system enclosuressuch as rack server chassis enclosures having one or more rows of harddrive assemblies. It is also possible that benefit of the disclosedsystems and methods may be realized in an information handling systemembodiment having as few as one of drive assemblies 400 (e.g., such asinternal to a desktop or laptop information handling system) that isprovided with lateral side-to-side cooling air flow through the openings480 and cavity 410 of the given drive assembly 400.

It will also be understood that the illustrated drive assemblyembodiment of FIGS. 4 and 5 is exemplary only, and that any otherconfiguration of open flow areas/s may be defined in opposing side walls436 and 438 of the base portion 460 of a drive assembly that is suitablefor allowing lateral side-to-side air flow through a cavity 410 definedin the base portion 460 of a drive assembly. For example, FIG. 7illustrates an alternate embodiment of a row of three mountable harddrive systems 550 that each include drive assemblies with openings 480in the form of multiple longitudinally-aligned rectangular notches orslots that are defined along the length of the bottom of the side railwithin each of side walls 436 and 438, and that are each in turn shownassembled to respective drive carrier assemblies 500 and mounted in arow to leave gaps 698 between the adjacent systems 550. It will beunderstood that the number, shape and dimensions of openings 480 may beselected to achieve and/or balance a desired air flow capacity withstructural integrity of side walls 436 and 438 of drive assemblies 400.In this regard, circular (e.g., drilled) openings 480 may providegreater structural integrity, while similarly sized rectangular notchesor slots may be easier to implement and may provide slightly greater airflow performance. In another exemplary embodiment, the pattern ofopenings 480 of FIG. 7 may be replaced by a single elongatedlongitudinal slot opening that spans the length of the opening patternof FIG. 7.

It will also be understood that the particular configuration of recessedopen area 580 that is illustrated defined in carrier side components 502and 504 of a drove carrier assembly 500 of FIGS. 5, 6A and 7 isexemplary only, and that any other suitable configuration of open area/smay be employed, including any pattern (number, size and/or shape) ofone or more opening/s, may be alternatively defined in side components502 and 504 that is suitable for at least partially or completelyoverlapping and/or aligning with one or more flow openings 480 definedin opposing side walls 436 and 438 of a base portion 460 of a driveassembly 400 that is to be mated and assembled to the given drivecarrier assembly 500 to form a mountable hard drive system 550. Forexample, in one alternate embodiment, separate and discrete openings maybe defined in in carrier side components 502 and 504 of a given drovecarrier assembly 500. And, in a further exemplary embodiment, suchseparate and discrete openings may be of similar shape, size and patternas the flow openings 480 defined in opposing side walls 436 and 438 of abase portion 460 of a drive assembly 400 to which the given drovecarrier assembly 500 is to be assembled. Similarly, it is also possiblethat a single recessed open area may be defined in each of the sidewalls 436 and 438 of a base portion 460 of a given drive assembly 400,e.g., to match or otherwise at least partially or completely overlapand/or align with a recessed open area defined in carrier sidecomponents 502 and 504 of a given drove carrier assembly 500 that is tobe mated and assembled to the given drive assembly 400.

FIG. 8 illustrates a graph of computational fluid dynamics (CFD)simulated air flow impedance (in inches or water) versus air flow rate(in cubic feet per minute) as measured across the front-to-back lengthof an enclosed dense storage enclosure for two different types ofmountable hard drive systems installed in multiple laterally orientedside-to-side rows within the dense storage enclosure with the side wallsof the drive assemblies oriented to face the front or rear of the driveenclosure in a manner similar to that illustrated in FIG. 5 or 6A and6B. For the test data, the dense storage enclosure included rear-mountedcooing fans that draw air from front-to-back across the installed drivesof the enclosure in a direction perpendicular to the side walls of theinstalled hard drive assemblies. As shown, one set of impedance data ismeasured for a set of conventional hard drive systems (includingconventional hard drive assemblies and mated conventional drive carrierassemblies such as illustrated in FIGS. 1 and 2) that are installed inmultiple side-to-side rows within the dense storage enclosure in amanner similar to that illustrated in FIG. 5. The other set of impedancedata is measured for a set of hard drive systems that include hard driveassemblies and mated drive carrier assemblies each configured withaligned side open areas according to the disclosed systems and methods,such as illustrated in FIGS. 4 and 5 and that are shown installed inmultiple rows within the dense storage enclosure in a manner similar tothat illustrated in FIGS. 6A and 6B.

The test data of FIG. 8 shows that for the same given flow impedance, agreater cooling air flow rate through the dense storage enclosure andacross the installed hard drive systems is achieved using the disclosedhard drive systems with aligned side open areas than is achieved withthe conventional hard drive systems. For example, at the same given airflow impedance of 2.5 inches of water, greater than a 10% increase inair flow is achieved using the hard drive systems configured withaligned side open areas (i.e., about 220 CFM compared to about 197 CFM).Additionally, lower air flow impedance may be achieved for the samegiven cooling air flow rate using the hard drive systems configured withaligned side open areas (i.e., about 2.5 inches of water compared toabout 3 inches of water at a flow rate of about 220 CFM).

For purposes of this disclosure, an information handling system mayinclude any instrumentality or aggregate of instrumentalities operableto compute, calculate, determine, classify, process, transmit, receive,retrieve, originate, switch, store, display, communicate, manifest,detect, record, reproduce, handle, or utilize any form of information,intelligence, or data for business, scientific, control, or otherpurposes. For example, an information handling system may be a personalcomputer (e.g., desktop or laptop), tablet computer, mobile device(e.g., personal digital assistant (PDA) or smart phone), server (e.g.,blade server or rack server), a network storage device, or any othersuitable device and may vary in size, shape, performance, functionality,and price. The information handling system may include random accessmemory (RAM), one or more processing resources such as a centralprocessing unit (CPU) or hardware or software control logic, ROM, and/orother types of nonvolatile memory. Additional components of theinformation handling system may include one or more disk drives, one ormore network ports for communicating with external devices as well asvarious input and output (I/O) devices, such as a keyboard, a mouse,touch screen and/or a video display. The information handling system mayalso include one or more buses operable to transmit communicationsbetween the various hardware components.

While the invention may be adaptable to various modifications andalternative forms, specific embodiments have been shown by way ofexample and described herein. However, it should be understood that theinvention is not intended to be limited to the particular formsdisclosed. Rather, the invention is to cover all modifications,equivalents, and alternatives falling within the spirit and scope of theinvention as defined by the appended claims. Moreover, the differentaspects of the disclosed systems and methods may be utilized in variouscombinations and/or independently. Thus the invention is not limited toonly those combinations shown herein, but rather may include othercombinations.

What is claimed is:
 1. A mountable hard drive system, comprising: a harddrive assembly comprising: a front end, a back end, and two opposingside walls extending between the front end and back end of the harddrive assembly, a bottom surface having a drive cavity defined thereinbetween the two opposing side walls, and at least one open area definedin each of the opposing side walls, the open area of each side wallbeing in fluid communication with the drive cavity; and a drive carrierassembly, comprising two opposing side rail components, each of the siderail components having at least one air flow area defined therein; whereeach given one of the two side rail components of the drive carrierassembly is mechanically coupled to a different one of the two opposingside walls of the hard drive assembly such that the open flow area ofthe given side rail component is at least partially aligned with theopen flow area of the given one of the opposing side walls of the harddrive assembly to form an air flow channel across the drive cavity ofthe hard drive assembly between the two opposing side walls and the twoopposing side rail components.
 2. The hard drive system of claim 1,where the open area defined in each of the given hard drive assemblyside walls comprises multiple air flow openings defined in the givenside wall; and where the open air flow defined in each given one of theside rail components of the drive carrier assembly comprises a recessedopen area.
 3. The hard drive system of claim 2, where the recessed openarea defined in each given one of the side rail components of the drivecarrier assembly completely overlaps the multiple air flow openingsdefined in a given one of the side rail components of the drive carrierassembly to which the given one of the of the side rail components ofthe drive carrier assembly is mechanically coupled.
 4. The hard drivesystem of claim 1, where the drive carrier assembly further comprises across member coupled between the two opposing side rail components; andwhere each given one of the side rail components of the drive carrierassembly is mechanically coupled to a given one of the side walls of thehard drive assembly such that the cross member is disposed adjacent therear end of the hard drive.
 5. The hard drive system of claim 1, wherethe hard drive assembly further comprises a printed circuit board (PCB)assembly disposed on the bottom surface of the hard drive assemblyadjacent the front end of the hard drive assembly; and where the drivecavity is defined in the bottom surface of the hard drive assemblybetween the PCB assembly and the back end of the hard drive assembly. 6.The hard drive system of claim 1, where the hard drive assembly furthercomprises: a top portion that includes a hermetically sealed space thatcontains the drive media and read/write arm (heads); and a base portionthat includes the bottom surface and drive cavity defined therein. 7.The hard drive system of claim 1, where the open area defined in each ofthe given hard drive assembly side walls comprises multiplecircular-shaped air flow holes.
 8. The hard drive system of claim 1,where the open area defined in each of the given hard drive assemblyside walls comprises multiple square-shaped or rectangular-shaped airflow slots.
 9. A hard drive enclosure system, comprising: at least onehard drive system mounted within the hard drive enclosure, the mountablehard drive system comprising a hard drive assembly and a drive carrierassembly mechanically coupled to the hard drive system; where the harddrive assembly comprises: a front end, a back end, and two opposing sidewalls extending between the front end and back end of the hard driveassembly, a bottom surface having a drive cavity defined therein betweenthe two opposing side walls, a top surface opposite the bottom surface,and at least one open area defined in each of the opposing side walls,the open area of each side wall being in fluid communication with thedrive cavity; where the drive carrier assembly comprises two opposingside rail components, each given one of the side rail components havingat least one air flow area defined therein and being mechanicallycoupled to a different one of the two opposing side walls of the harddrive assembly such that the open flow area of the given side railcomponent is at least partially aligned with the open flow area of thegiven one of the opposing side walls of the hard drive assembly to forman air flow channel across the drive cavity of the hard drive assemblybetween the two opposing side walls and the two opposing side railcomponents; where the hard drive enclosure system further comprises:multiple enclosure walls surrounding the hard drive system, and acooling air flow source configured to induce lateral side-to-side flowof cooling air through the flow channel of the hard drive system acrossthe drive cavity of the hard drive assembly between the two opposingside walls and the two opposing side rail components.
 10. The hard driveenclosure system of claim 9, where at least one hard drive systemcomprises at least one row of two or more of the hard drive systemsmounted in top-to-bottom aligned relationship with each other thereinsuch that the cooling air flow source is configured to induce lateralside-to-side flow of cooling air through the flow channel of each of thetwo or more hard drive systems across the drive cavity of the hard driveassembly of each given one of the two or more hard drive systems betweenthe two opposing side walls and the two opposing side rail components ofeach given one of the two or more hard drive systems.
 11. The hard driveenclosure system of claim 9, where at least one hard drive systemcomprises multiple rows of two or more of the hard drive systems mountedin top-to-bottom aligned relationship with each other therein such thatthe cooling air flow source is configured to induce lateral side-to-sideflow of cooling air through the flow channel of each given one of thetwo or more hard drive systems of each of the multiple rows across thedrive cavity of the hard drive assembly of each given one of the two ormore hard drive systems of each of the multiple rows of hard drivesystems.
 12. The hard drive enclosure system of claim 11, where themultiple rows of two or more hard drive systems are arranged so that theside walls of the individual hard drive systems of a first one of themultiple rows of hard drive systems faces the side walls of theindividual hard drive systems of an adjacent second one of the multiplerows of hard drive systems, and such that the cooling air flow source isconfigured to induce lateral side-to-side flow of cooling air firstthrough the flow channel of each given one of the two or more hard drivesystems of the first one of the multiple rows of hard drive systems andthen subsequently through the flow channel of each given one of the twoor more hard drive systems of the second one of the multiple rows ofhard drive systems.
 13. The hard drive enclosure system of claim 11,where the multiple rows of two or more hard drive systems are mountedwithin the enclosure such that the open areas of the hard drive systemsof a first one of the multiple rows of hard drive systems arelongitudinally aligned with the open areas of the hard drive systems ofa second and adjacent one of the multiple rows of hard drive systems soas to allow substantially direct passage of cooling air from an openarea of each of the of the hard drive systems of the first one of themultiple rows of hard drive systems to an open area of a respective oneof the of the hard drive systems of the second and adjacent one of themultiple rows of hard drive systems.
 14. The hard drive enclosure systemof claim 11, where the adjacent hard drive systems of each of themultiple rows of two or more hard drive systems are mounted intop-to-bottom aligned relationship with each other within the enclosurewith substantially no gap therebetween.
 15. The hard drive enclosuresystem of claim 11, further comprising: first and second opposing endswith the multiple rows of two or more of hard drive systems disposedtherebetween; an air inlet being disposed adjacent the first end of theenclosure; and an air outlet being disposed adjacent the second end ofthe enclosure; where the cooling air flow source comprises one or morecooling fans disposed adjacent the second end of the enclosure andconfigured to induce a flow of the cooling air from the air inlet of theenclosure through the flow channel and drive cavity of each given one ofthe two or more hard drive systems of each of the multiple rows of harddrive systems to the air outlet of the enclosure.
 16. The hard driveenclosure system of claim 11, where the hard drive enclosure comprises adense storage drive enclosure.
 17. The hard drive enclosure system ofclaim 11, where the hard drive enclosure comprises a rack server chassisenclosure.
 18. A method of cooling at least one mountable hard drivesystem, the method comprising providing cooling air to a mountable harddrive system that itself comprises: a hard drive assembly comprising: afront end, a back end, and two opposing side walls extending between thefront end and back end of the hard drive assembly, a bottom surfacehaving a drive cavity defined therein between the two opposing sidewalls, and at least one open area defined in each of the opposing sidewalls, the open area of each side wall being in fluid communication withthe drive cavity; and a drive carrier assembly, comprising two opposingside rail components, each of the side rail components having at leastone air flow area defined therein; where each given one of the two siderail components of the drive carrier assembly is mechanically coupled toa different one of the two opposing side walls of the hard driveassembly such that the open flow area of the given side rail componentis at least partially aligned with the open flow area of the given oneof the opposing side walls of the hard drive assembly to form an airflow channel across the drive cavity of the hard drive assembly betweenthe two opposing side walls and the two opposing side rail components;and where the method further comprises using a cooling air flow sourceto induce lateral side-to-side flow of cooling air through the flowchannel of the hard drive system across the drive cavity of the harddrive assembly between the two opposing side walls and the two opposingside rail components.
 19. The method of claim 18, where at least onehard drive system comprises multiple rows of two or more of the harddrive systems mounted in top-to-bottom aligned relationship with eachother within a hard drive enclosure system; and where the method furthercomprises using the cooling air flow source to induce lateralside-to-side flow of cooling air through the flow channel of each givenone of the two or more hard drive systems of each of the multiple rowsacross the drive cavity of the hard drive assembly of each given one ofthe hard drive systems.
 20. A drive carrier assembly configured formechanically coupling to a hard drive assembly to form a mountable harddrive system, the drive carrier system comprising: two opposing siderail components, each of the side rail components having at least oneair flow area defined therein; where each given one of the two side railcomponents of the drive carrier assembly is configured to bemechanically coupled to a different one of two opposing side walls of ahard drive assembly that itself has: a front end, a back end, and twoopposing side walls extending between the front end and back end of thehard drive assembly, a bottom surface having a drive cavity definedtherein between the two opposing side walls, and at least one open areadefined in each of the opposing side walls, the open area of each sidewall being in fluid communication with the drive cavity; and where eachgiven one of the two side rail components of the drive carrier assemblyis configured to be mechanically coupled to a different one of the twoopposing side walls of the hard drive assembly such that the open flowarea of the given side rail component is at least partially aligned withthe open flow area of the given one of the opposing side walls of thehard drive assembly to form an air flow channel across the drive cavityof the hard drive assembly between the two opposing side walls and thetwo opposing side rail components.